Two capillary tubes A and B of diameter $1\, mm$ and $2\, mm$ respectively are dipped vertically in a liquid. If the capillary rise in A is 6 cm, then the capillary rise in B is
- 2 cm
- 3 cm
- 4 cm
- 6 cm
The Correct Option is B
Solution and Explanation
Diameters of capillary tube, $B=2\, mm$
and $h_{1}=6\, m$
We know that, $h_{1} I_{1}=h_{2} I_{2}$
$\Rightarrow 6 \times 1=h_{2} \times 2$
$\Rightarrow$ Capilliary rise in tube $B$,
$h_{2}=\frac{6}{2}=3\, cm$
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Concepts Used:
Surface Tension
The amount of energy required to increase the liquid's surface area by one unit area is known as surface tension. In other words, it is a property of the liquid surface to resist force.
Surface tension is defined as,
The ratio of the surface force F to the length L along which the force acts.
Mathematically, the surface tension formula can be expressed as follows:
T=F/L
Where,
- F is the force per unit length
- L is the length in which force act
- T is the surface tension of the liquid
Read More: Detergents and Surface Tension
Factors affecting surface tension:
- Impurities: The surface tension decreases with the addition of impurities.
- Surfactants: Adding surfactants in liquids lowers the tension of water making it interrupt aside or get susceptible.
- Temperature: The surface tension of a liquid reduces as the temperature rises.
The Unit of Surface Tension:
The SI unit of Surface Tension is Newton per Meter or N/m.